The present invention relates to a rail-mounted transport system, in particular an overhead monorail, comprising at least one active track switch, which comprises at least two movable rail portions that are selectively bringable into an operating position, in which the movable rail portion situated in the operating position connects in each case two fixed rail portions of the transport system to one another, and comprising at least one vehicle, which is movable along the rail portions of the transport system and comprises at least one power transmission unit for the contact-free transmission of power from power supply lines of the transport system to the vehicle.
Such rail-mounted transport systems, in particular overhead monorails, are known from prior art.
Here, by a “active track switch” is meant a switch having movable rail portions, whereas in the case of a “passive track switch” all of the rail portions are stationary and, instead, the rail portion to be travelled along by the vehicle is selected by switching over a guide device provided on the vehicle.
An active track switch for an overhead monorail are known e.g. from DE 33 02 266 C2. In the overhead monorail known from DE 33 02 266 C2 the power required for operation is supplied to the vehicles of the overhead monorail via carbon brushes, which are disposed on the vehicle and in electrically conductive contact with collector conductors running along the running rails of the overhead monorail. The movable rail portions of the active track switch of said overhead monorail are also provided with such collector conductors, which have to be connected by means of flexible trailing cables to a stationary power source in order to enable the mobility of the movable rail portions.
In an overhead monorail with a contacting power supply such a coupling of the movable rail portions of an active track switch to a stationary power source may be effected relatively easily and reliably because such an overhead monorail is operated with alternating current of a low frequency (usually 50 Hz or 60 Hz).
In a rail-mounted transport system with contact-free, e.g. inductive, transmission of power from the power supply lines to the vehicles of the transport system, however, such flexible cabling in active track switches is very costly since such transport systems are operated with alternating current in the medium frequency range (e.g. 25 kHz) and therefore flexible cables suitable for medium-frequency currents have to be used for the power supply to the active track switch. If, in addition to a power supply to the vehicles, the transmission of data to the vehicles in the region of the active track switch is desired, then flexible high-frequency cables (for transmitting currents in the MHz range or even in the GHz range) have to be additionally provided. Highly flexible medium-frequency and high-frequency cables are, however, complicated and expensive to manufacture.